A Polymer Dispresion System for Use in a Hydraulic Fracturing Operation

ABSTRACT

A polymer dispersion system for use in a hydraulic fracturing operation is disclosed. The system comprises: (a) a first sub-system comprising an ingress and an egress; (b) a second sub-system comprising an ingress and an egress; (c) an eductor mixing device comprising a first inlet in fluid communication with the egress of the first sub-system, a second inlet in fluid communication with the egress of the second subsystem, and an egress; (d) a tank assembly comprising an ingress and an egress, the ingress of the tank assembly being in fluid communication with the egress of the eductor mixing device; and (e) a transfer sub-system comprising an ingress that is coupled to the egress of the tank assembly. The transfer sub-system comprises a first transfer pump and a second transfer pump. In addition, method for operating the polymer dispersion system is disclosed.

CROSS-REFERENCE

The present application is a continuation-in-part application ofapplication Ser. No. 16/809,398 filed Sep. Mar. 4, 2020, entitled“SYSTEM AND METHOD FOR PREPARING A COMPOSITION” currently pending, thecontent of which is incorporated herein in its entirety.

TECHNICAL FIELD

The present disclosure relates to a polymer dispersion system for use ina hydraulic fracturing operation in the oil and gas industry.

BACKGROUND

Use of subterranean formation treatment fluids (e.g. polymer hydraulicfracturing fluids) is a common practice in a hydraulic fracturingoperation in the oil and gas industry. Such fluids not only make itpossible to reduce fracturing injection pressures, but also serve toreduce frictional forces in the injection pipes that may otherwise bepresent if other fracturing fluids or no fracturing fluids were used.The preparation of polymer hydraulic fracturing fluids, on demand and atthe site of the hydraulic fracturing operation, and how such fracturingfluids are prepared are a continual point of interest to those active inthe oil and gas industry.

The preparation of polymer hydraulic fracturing fluids can be donethrough apparatuses and systems commonly referring to as “polymerdissolution equipment”. Examples of such pieces of equipment have beenpreviously discussed in the patent literature (see for example,International application number PCT/EP2009/063961, Internationalapplication number PCT/FR2011/050262, and U.S. Pat. No. 9,067,182). Suchprior art pieces of equipment generally comprise a “polymer slicingunit”, and such unit generally comprises a rotor driven by a motor, andblades for mixing and grinding the polymer into a solvent in order toform a polymer emulsion that is either the polymer hydraulic fracturingfluid or a component of the polymer hydraulic fracturing fluid. Anexample of a “polymer slicing unit” can be found in internationalapplication number PCT/EP2008/053495.

A polymer dissolution equipment comprising a polymer slicing unitsuffers from potential drawbacks including wear and tear and breakdownof mechanical parts within the unit. Given that the preparation ofpolymer hydraulic fracturing fluids is a highly intensive and mechanicprocess, the polymer slicing unit is a component of a polymerdissolution equipment that requires frequent replacement. Such breakdownof equipment may lead to delays in hydraulic fracturing operations andmay result in loss opportunity or revenue. In addition, the amount ofpolymer that can be liquefied into a solvent to form the fracturingfluid is also limited by the mechanical limitations of a polymer slicingunit.

To circumvent the potential foregoing issues with polymer dissolutionequipment comprising a polymer slicing unit, some polymer dissolutionequipment replace the polymer slicing unit with an eductor mixing device(e.g. U.S. Pat. No. 7,794,135). While it had been previously noted thateductor mixing devices suffer from some disadvantages such as largeenergy consumption, excessive noise, and energy inefficiencies (e.g.United States Pub. No. 2010/0220549), such perceived disadvantages havelargely been or can largely be mitigated through advances to the eductormixing devices themselves.

Regardless of the polymer dissolution equipment used within a polymerdispersion system, however, many existing polymer dispersion systemscontinue to suffer from long “down” periods when a component within thesystem malfunctions or when a portion of the system is taken “offline”for maintenance or repair. Disclosed herein is a polymer dispersionsystem that may mitigate operational losses associated with equipment“down” time or “offline” periods.

SUMMARY

As described in a part of the present disclosure, there is a polymerdispersion system comprising: (a) a first sub-system comprising aningress and an egress; (b) a second sub-system comprising an ingress andan egress; (c) an eductor mixing device comprising (i) a first inlet influid communication with the egress of the first sub-system, (ii) asecond inlet in fluid communication with the egress of the secondsub-system, and (iii) an egress; (d) a tank assembly comprising aningress and an egress, the ingress of the tank assembly being in fluidcommunication with the egress of the eductor mixing device; and (e) atransfer sub-system comprising an ingress that is coupled to the egressof the tank assembly.

The first sub-system is used for receiving a liquid medium and fordirecting the liquid medium towards the eductor mixing device, thesecond sub-system is used for receiving a particulate material and fordirecting the particulate material towards the eductor mixing device,the first inlet of the eductor mixing device is for receiving the liquidmedium from the first sub-system, the second inlet of the eductor mixingdevice is for receiving the particulate material from the secondsub-system, the eductor mixing device is capable of generating anegative pressure for drawing the liquid medium and the particulatematerial into the eductor mixing device, the eductor mixing device isused for mixing the liquid medium and the particulate material by vortexto form a mother solution, and the tank assembly is used for receivingthe mother solution.

The first sub-system further comprises a line for transporting theliquid medium. The line comprises a plurality of segments including: (a)a first segment comprising an ingress which is also the ingress of thefirst sub-system, and an egress; (b) a second segment comprising aningress and an egress, the ingress of the second segment being coupledto the egress of the first segment, the second segment comprising afirst pump that is disposed between the ingress and egress of the secondsegment; and (c) a third segment comprising an ingress and an egress,the ingress of the third segment being coupled to the egress of thefirst segment, the third segment comprising a second pump that isdisposed between the ingress and egress of the third segment.

The second sub-system comprises: (a) a containing unit for containingthe particulate material, the containing unit comprising an egress; (b)a feeder unit comprising an ingress that is coupled to the egress of thesilo assembly via a conduit; and (c) a conveying unit in fluidcommunication with an egress of the feeder unit, and for receiving theparticulate material from the feeder unit, the conveying unit in fluidcommunication with the eductor mixing device.

The containing unit comprises: (a) a level meter for controlling thevolume of the particulate material introduced through the egress of thecontaining unit and into the feeder unit; and (b) a vibrator foragitating the particulate material that is contained in the containingunit.

The conveying unit is in fluid communication with a dust collectionunit, and the dust collective unit for receiving any particulatematerial that is not received into the feeder unit.

The eductor mixing device is in fluid communication with the conveyingunit.

The interior surface of one or more parts of the second sub-system maybe coated with a non-stick coating.

One or more parts of the second sub-system may be coupled to a heatingdevice.

The tank assembly may further comprise an overflow pipe that is in fluidcommunication with an interior volume of the tank assembly, the overflowpipe for receiving excess mother solution that cannot be containedwithin the tank assembly.

The tank assembly comprises an egress that is coupled to the transfersub-system by a conduit. The transfer sub-system further comprises afirst transfer pump and a second transfer pump, both of which arecoupled to an egress of the tank assembly.

The tank assembly further may further comprise a liquid level meter forregulating the volume of the mother solution flowing towards the firsttransfer pump, the second transfer pump, or both.

The first transfer pump may be a low pressure pump, and the secondtransfer pump may be a high pressure pump.

The operation of the polymer dispersion system is controlled by aprogrammable logic controller sub-system.

As described in another part of the disclosure, there is a method ofoperating a polymer dispersion system, the method comprising: (a)receiving a liquid medium in a first sub-system of the polymerdispersion system; (b) receiving a particulate material in a secondsub-system of the polymer dispersion system; (c) introducing the liquidmedium and the particulate material into an eductor mixing device thatis in fluid communication with an egress of the first sub-system and anegress of the second sub-system; (d) mixing the liquid medium and theparticulate material by vortex to form a mother solution; and (e)directing the mother solution to the first transfer pump, the secondtransfer pump, or both.

As described in another part of the disclosure, there is a system foruse in a hydraulic fracturing operation, the system comprising; (a) atank assembly comprising an ingress and an egress; (b) a first transferpump in fluid communication with the egress of the tank assembly; and(c) a second transfer pump in fluid communication with the egress of thetank assembly; wherein the second transfer pump has a pump volumecapacity that is greater than the first transfer pump; and wherein thesecond transfer pump is configured to operate at a higher pump pressurethan the first transfer pump.

As described in another part of the disclosure, there is a system foruse in a hydraulic fracturing operation, the system comprising: (a) atank assembly comprising an ingress and an egress; (b) a first transferpump in fluid communication with the egress of the tank assembly; and(c) a second transfer pump in fluid communication with the egress of thetank assembly; wherein the second transfer pump has a pump volumecapacity that is greater than the first transfer pump; and wherein thesecond transfer pump is configured to operate at a higher pump pressurethan the first transfer pump. The system further comprises: (d) a firstsub-system comprising an ingress and an egress; (e) a second sub-systemcomprising an ingress and an egress; and (f) one or more eductor mixingdevice, each one or more eductor mixing device comprising (i) a firstinlet in fluid communication with the egress of the first sub-system,(ii) a second inlet in fluid communication with the egress of the secondsub-system, and (iii) an egress in fluid communication with the ingressof the tank assembly. The first sub-system is configured to receiveliquid medium and to transport same towards the one or more eductormixing device. The second sub-system is configured to receiveparticulate material and to transport same towards the one or moreeductor mixing device. The first inlet of each one or more eductormixing device is configured to receive liquid medium from the firstsub-system. The second inlet of each one or more eductor mixing deviceis configured to receive particulate material from the secondsub-system. Each one or more eductor mixing device is capable ofgenerating a negative pressure for drawing liquid medium and particulatematerial into said eductor mixing device. Each one or more eductormixing device is for mixing liquid medium and particulate material byvortex for forming mother solution.

This summary does not necessarily describe the entire scope of allaspects of the disclosure. Other aspects, features and advantages willbe apparent to those of ordinary skill in the art upon review of thefollowing description of specific embodiments.

BRIEF DESCRIPTION OF DRAWINGS

In the accompanying drawings, which illustrate one or more embodiments:

FIG. 1 is a schematic view of a polymer dispersion system (1000)comprising a water intake sub-system (1100), a dry materials intakesub-system (1200), an eductor mixing sub-system (1300) for mixing waterand dry material to form a mother solution, a plurality of pumps (1320,1330) that are downstream of the eductor mixing sub-system (1300) foruse in injecting mother solution towards further downstream hydraulicfracturing operations, and a programmable logic controller (1400) forcontrolling the various components of the polymer dispersion system(1000). The stippled lines therein represent communication pathwaysbetween the programmable logic controller (1400) and the variouscomponents of the polymer dispersion system (1000). FIG. 1 furthercomprises a legend describing various valves and frequency convertersthat are disposed in a plurality of locations within the polymerdispersion system.

DETAILED DESCRIPTION

Directional terms such as “top,” “bottom,” “upwards,” “downwards,”“vertically,” and “laterally” are used in the following description forthe purpose of providing relative reference only, and are not intendedto suggest any limitations on how any article is to be positioned duringuse, or to be mounted in an assembly or relative to an environment. Theuse of the word “a” or “an” when used herein in conjunction with theterm “comprising” may mean “one,” but it is also consistent with themeaning of “one or more,” “at least one” and “one or more than one.” Anyelement expressed in the singular form also encompasses its plural form.Any element expressed in the plural form also encompasses its singularform. The term “plurality” as used herein means more than one, forexample, two or more, three or more, four or more, and the like.

As used herein, the term “about”, when used to describe a recited value,means within 5% of the recited value.

As used herein, the terms “comprising,” “having,” “including” and“containing,” and grammatical variations thereof, are inclusive oropen-ended and do not exclude additional, un-recited elements and/ormethod steps. The term “consisting essentially of” when used herein inconnection with a composition, use or method, denotes that additionalelements, method steps or both additional elements and method steps maybe present, but that these additions do not materially affect the mannerin which the recited composition, method or use functions. The term“consisting of” when used herein in connection with a composition, useor method, excludes the presence of additional elements and/or methodsteps.

As used herein, the term “low shear” refers to any applied force orstress within a range of forces and stresses than does not cause greaterthan 2% degradation of polymeric material in the “mother solution”.

As used herein, the term “connected” may refer to any one of reversiblecoupling (e.g. nuts and bolts), irreversible coupling to (e.g. throughwelding), or two or more defined portions of an other integral object(e.g. the openings and extensions therefrom of an integral pipe elbow).

As used herein, the term “PLC” means programmable logic controller.

As used herein, the term “segment” in reference to water line 1100,refers to a portion of water line 1100. For example, water line 1100 maycomprise of a plurality of discrete pipes each coupled to one another bymeans known in the art (e.g. reversible coupling like nuts and bolts orirreversible coupling like welding). Such pipes may described herein asa “segment”,

As used herein, the term “substantially” is intended to contemplate anyand all variations or deviations of an art, process, value, machine,manufacture or composition of matter that are not of material effect.

Described in the present disclosure is a polymer dispersion system forpreparing a polymer hydraulic fracturing fluid. The polymer dispersionsystem comprises: (a) a first sub-system comprising an ingress and anegress; (b) a second sub-system comprising an ingress and an egress; (c)an eductor mixing device comprising (i) a first inlet in fluidcommunication with the egress of the first sub-system, (ii) a secondinlet in fluid communication with the egress of the second sub-system,and (iii) an egress; (d) a tank assembly comprising an ingress and anegress, the ingress of the tank assembly being in fluid communicationwith the egress of the eductor mixing device; and (e) a transfersub-system comprising an ingress that is coupled to the egress of thetank assembly. The liquid medium can be any suitable liquid medium orcombination of suitable liquid media known in the art, such as water. Anexample of the first sub-system is a sub-system that is designed toreceive a liquid medium, such as a water intake sub-system that isdesigned to direct water towards the eductor mixing device. An exampleof the second sub-system is a sub-system that is designed to receive adry material (e.g. polymer in dry form). The eductor mixing device isused for mixing the liquid medium and the polymer in dry form togetherto form a polymer emulsion (also referred to as a “mother solution”).The tank assembly is for containing the formed polymer emulsion.

The system may further comprise a transfer sub-system that can be influid communication with the tank assembly. The transfer sub-system maybe adapted to transfer a polymer emulsion to a blender unit, a missileunit, or both. The blender unit may mix the mother solution with asecond material (e.g. sand) to form a polymer hydraulic fracturingfluid. The missile unit delivers the polymer hydraulic fracturing fluiddownhole for use in a hydraulic fracturing operation. In other versionsof the system, the mother solution is the polymer hydraulic fracturingfluid (i.e. the mother solution does not undergo further mixing), andthe mother solution is delivered directly to the missile unit and notfurther blended in the blender unit. The system is controlled andoperated via a programmable logic controller. The system is alsoconnected, or can be connected, to a sewage outlet (e.g. sewage outlet“S” as depicted in FIG. 1) or other external holding tank. The systemmay be portable and mobile, and may be brought onto the site of thehydraulic fracturing operation.

Polymer Dispersion System

According to an embodiment of the system, and referring to FIG. 1, thereis a system 1000 comprising a water intake sub-system 1100, a polymerintake sub-system 1200, and an eductor mixing device 1300. System 1000further comprises a plurality of valves disposed at various suitablelocations within system 1000, the plurality of valves for regulating theflow of materials (e.g. water, polymer, polymer emulsion) through system1000. Examples of suitable valves include throttle valves 1101, safetyvalves 1102, ball valves 1103, electric valve 1104, disc valves 1105,shut-off valves 1106, check valves 1107, and any combination thereof.The location of the plurality of valves, according to this embodiment,is depicted in FIG. 1. In other embodiments, the valves may be disposedwithin the system at other suitable locations. PLC 1400 is adapted tocontrol various aspects and components of system 1000 for ensuringoperation of system 1000.

Water Intake Sub-System

Water intake sub-system 1100 is a first sub-system of system 1000.Sub-system 1100 comprises a water line 1110 for receiving water intosub-system 1100 and for transporting water through sub-system 1100 andtowards eductor mixing device 1300. Water line 1110 comprises an inlet1110 a for receiving water, and an outlet 1110 b directed toward and influid communication with an ingress of eductor mixing device 1300. Waterline 1110 is made up of a plurality of water line segments coupledtogether. First water line segment 1111 comprises an ingress that isalso inlet 1110 a and an egress that is in fluid communication with (i)an ingress of second water line segment 1112, and (ii) an ingress ofthird water line segment 1113. First water line segment 1111 is fordirecting water towards second water line segment 1112 and third waterline segment 1113. First water line segment 1111 is placed in serieswith second water line segment 1112 and third water line segment 1113.Second water line segment 1112 is placed in parallel with third waterline segment 1113.

As contemplated in this embodiment, first water line segment 1111comprises a pressure meter 1111 a for measuring water pressure withinfirst water line segment 1111. Pressure meter 1111 a is in communicationwith PLC 1400, and sends collected data related to the water pressure infirst water line segment 1111 in real-time to PLC 1400. In otherembodiments, the first water line segment may not comprise a pressuremeter.

Second water line segment 1112 is connected to a first water supply pump1120 a. First water supply pump 1120 a serves the purpose of pumpingwater present in water line 1110 through sub-system 1100 and towardseductor mixing device 1300. The water supply pump can be any watersupply pump that is known in the art and fit for an application forproducing polymer hydraulic fracturing fluids. As contemplated in thisembodiment, first water supply pump 1120 a has a volume of over 300litres and is capable of processing 50 cubic metres of water per hour.Second water line segment 1112, itself, can be divided into two parts:(i) a first part 1112 a that leads towards first water supply pump 1120a, and (H) a second part 1112 b that leads away from first water supplypump 1120 a.

Third water line segment 1113 is connected to a second water supply pump1120 b. Second water supply pump 1120 b serves the purpose of pumpingwater present in water line 1110 through sub-system 1100 and towardseductor mixing device 1300 in the event that first water supply pump1120 a becomes inoperative. The water supply pump can be any watersupply pump that is known in the art and fit for purpose for producingpolymer hydraulic fracturing fluids. As contemplated in this embodiment,second water supply pump 1120 a has a volume of over 300 litres and iscapable of processing 50 cubic metres of water per hour. Third waterline segment 1113, itself, can be divided into two parts: (i) a firstpart 1113 a that leads towards second water supply pump 1120 b, and (ii)a second part 1113 b that leads away from second water supply pump 1120b.

As contemplated in this embodiment, third water line segment 1113 andsecond water supply pump 1120 b serve as a “back-up” for second waterline segment 1112 and first water supply pump 1120 a, in the event thatsecond water line segment 1112 and first water supply pump 1120 a becomeinoperative or are taken “offline” (e.g. for repair, maintenance, orother reasons). In practice, when first water supply pump 1120 a becomesinoperative or is taken “offline”, PLC 1400 directs a signal to closethe valve (depicted as a disc valve 1105 in FIG. 1) disposed upstream ofthe ingress of first water supply pump 1120 a in part 1112 a and anothersignal to open the valve (depicted as a disc valve 1105 in FIG. 1)disposed upstream of the ingress of second water supply pump 1120 b inpart 1113 a, thereby preventing water in water line 1110 from furtheraccessing first water supply pump 1120 a and diverting water in waterline 1110 to first part 1113 a and towards second water supply pump 1120b. Conversely, when first water supply pump 1120 a is ready to become“online” again, PLC 1400 directs a signal to close the valve (depictedas a disc valve 1105 in FIG. 1) disposed upstream of the ingress ofsecond water supply pump 1120 b in part 1113 a and another signal toopen the valve (depicted as a disc valve 1105 in FIG. 1) disposedupstream of the ingress of first water supply pump 1120 a in part 1112a, thereby preventing water in water line 1110 from further accessingsecond water supply pump 1120 b and diverting water in water line 1110to first part 1112 a and towards first part water supply pump 1120 a. Insome embodiments, such as the embodiment depicted in FIG. 1, valves(such as disc valves 1105) are disposed downstream of the egresses offirst water supply pump 1120 a in part 1112 b and second water supplypump 1120 b in part 1113 b for the purposes of further limiting any flowof water through: (i) water line segment 1112 when pump 1120 a is“offline”; and (ii) water line segment 1113 when pump 1120 b is“offline”.

The combination of second water line segment 1112 and third water linesegment 1113 also provides a “split flow” function whereby water isdirected to both water line segments 1112 and 1113 and towards bothsupply pumps 1120 a and 1120 b. The “split flow” arrangementadvantageously minimizes the likelihood that any one of supply pumps1120 a and 1120 b will be overworked or overused while system 1000 is inoperation.

As contemplated in this embodiment, first water supply pump 1120 a andsecond water supply pump 1120 b are each connected to a waste tank 1140that is used for collecting excess water that may be drained from pumps1120 a and 1120 b. Waste tank 1140 is connected to a waste line (notnumbered) that leads to sewage outlet “S” or an external holding tank(not shown).

Second part 1112 b of second water line segment 1112 and second part1113 b of third water line segment 1113 are both connected to and influid communication with four water line segment 1114, which is asegment of water line 1110. Fourth water line segment 1114 comprises (i)an ingress that is in fluid communication with both second part 1112 bof second water line segment 1112 and second part 1113 b of third waterline segment 1113, and (ii) an egress. As contemplated in thisembodiment, fourth water line segment 1114 comprises a pressure meter1114 a for measuring water pressure within fourth water line segment1114. Pressure meter 1114 a is in communication with PLC 1400, and sendscollected data in real-time to PLC 1400. If the data collected frompressure meter 1114 a is above or below In other embodiments, the fourthwater line segment may not comprise a pressure meter.

The egress of fourth water line segment 1114 is in fluid communicationwith (i) an ingress of fifth water line segment 1115, and (ii) aningress of sixth water line segment 1116, Fourth water line segment 1114is for directing water towards fifth water line segment 1115 and sixthwater line segment 1116.

Fifth water line segment 1115 can be divided into two parts: (i) a firstpart 1115 a, and (ii) a second part 1115 b. The two parts of fifth waterline segment 1115 are separated by a filter 1130 a Filter 1130 afunctions to remove particles from water that may adversely impact thepreparation of a fracturing fluid. Filter 1130 a can be any suitablefilter known in the art. A non-limiting example of a suitable filter isa hydraulic filter. The pore size of filter 1130 a can be any suitablesize, provided that it fulfils its function of removing particles fromwater that may adversely impact the preparation of a fracturing fluid.For example, the pore size of filter 1130 a can be between about 1microns and about 1000 microns. For example, suitable pore sizesinclude, but are not limited to, about 1 μm, about 10 μm, about 100 μm,about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm,about 700 μm, about 800 μm, about 900 μm, about 1000 μm, As contemplatedin this embodiment, filter 1130 a has a pore size of about 200 μm.

Sixth water line segment 1116 can be divided into two parts: (i) a firstpart 1116 a, and (ii) a second part 1116 b. The two parts of sixth waterline segment 1116 are separated by a filter 1130 b. Filter 1130 bfunctions to remove particles from water that may adversely impact thepreparation of a fracturing fluid, Filter 1130 b can be any suitablefilter known in the art. A non-limiting example of a suitable filter isa hydraulic filter. The pore size of filter 1130 b can be any suitablesize, provided that it fulfils its function of removing particles fromwater that may adversely impact the preparation of a fracturing fluid.For example, the pore size of filter 1130 b can be between about 1microns and about 1000 microns, For example, suitable pore sizesinclude, but are not limited to, about 1 μm, about 10 μm, about 100 μm,about 200 μm, about 300 μm, about 400 μm, about 500 μm, about 600 μm,about 700 μm, about 800 μm, about 900 μm, about 1000 μm.

As contemplated in this embodiment, water line segment 1116 and filter1130 b serve as a “back-up” for water line segment 1115 and filter 1130a, in the event that water line segment 1115 and filter 1130 a becomeinoperative or are taken “offline” (e.g. for repair, maintenance, orother reasons). In practice, when filter 1130 a becomes inoperative oris taken “offline”, PLC 1400 directs a signal to close the valve(depicted as a disc valve 1105 in FIG. 1) disposed upstream of theingress of filter 1130, in part 1115 a and another signal to open thevalve (depicted as a disc valve 1105 in FIG. 1) disposed upstream of theingress of filter 1130 a in part 1116 a, thereby preventing water inwater line 1110 from further accessing filter 1130 a and diverting waterin water line 1110 to part 1116 a and towards filter 1130 b. Conversely,when filter 1130 a is ready to become “online” again, PLC 1400 directs asignal to close the valve (depicted as a disc valve 1105 in FIG. 1)disposed upstream of the ingress of filter 1130 b in part 1116 a andanother signal to open the valve (depicted as a disc valve 1105 inFIG. 1) disposed upstream of the ingress of filter 1130 a in part 1115a, thereby preventing water in water line 1110 from further accessingfilter 1130 b and diverting water in water line 1110 to part 1115 a andtowards filter 1130 a. In some embodiments, such as the embodimentdepicted in FIG. 1, valves (such as disc valves 1105) are disposeddownstream of the egresses of filter 1130 a and filter 1130 b for thepurposes of further limiting any flow of water through: (i) water linesegment 1115 when filter 1130 a is “offline”; and (ii) water linesegment 1116 when filter 1130 b is “offline”. As contemplated in thisembodiment, filter 1130 a and filter 1130 b are each connected to awaste line (not numbered) that leads to sewage outlet “S” or an externalholding tank (not shown).

The combination of the water line segments 1115 and 1116 also provides a“split flow” function whereby water is directed to both water linesegments 1115 and 1116 and towards both filters 1130 a and 1130 b. The“split flow” arrangement advantageously minimizes the likelihood thatany one of filters 1130 a and 1130 b will be overworked or overusedwhile system 1000 is in operation.

Second part 1115 b of fifth water line segment 1115 and second part 1116b of sixth water line segment 1116 are both connected to and in fluidcommunication with seventh water line segment 1117, which is a segmentof water line 1110. Seventh water line segment 1117 comprises (i) aningress that is in fluid communication with both second part 1115 b offifth water line segment 1115 and second part 1116 b of sixth water linesegment 1116, and (ii) an egress. The egress of seventh water linesegment 1117 (i.e. outlet 1110 b) is directed toward and in fluidcommunication with an ingress of eductor mixing device 1300. Seventhwater line segment 1117 is for directing water towards eductor mixingdevice 1300. As contemplated in this embodiment, seventh water linesegment 1117 comprises one or more pressure monitors 1117 a, and one ormore flow meters 1117 b. The one or more pressure monitors 1117 a, andone or more flow meters 1117 b are in constant communication with PLC1400. Should the pressure monitor readings or the flow meter readingsdeviate from the reference values at the PLC 1400, PLC 1400 shall adjustany and all parameters of first sub-system 1100 including, but notlimited to, water intake rate at the ingress of water line 1110 and theopening or closing of valves disposed along water line 1110, so that theappropriate pressure and flow rate of water exiting egress 1110 b andinto eductor mixing device 1300 are met.

Disposed within first sub-system 1100 are a plurality of valves, each ofwhich is communicative with PLC 1400 and receives instructions from PLC1400 as to, for example, whether such valves should be open, closed, orpartially open (and if so to what degree). As depicted in FIG. 1: (i) aball valve 1103 is disposed along first water line segment 1111; (ii)disc valves 1105 are disposed along the first and second parts of secondwater line segment 1112, the first and second parts of third water linesegment 1113, the first and second parts of fifth water line segment1115, and the first and second parts of sixth water line segment 1116;(iii) a check valve 1107 is disposed along fourth water line segment1114; and (iv) a throttle valve 1101 and an electric valve 1104 aredisposed in series along seventh water line segment 1117. In otherembodiments, valves may be arranged in different sequences and orders.

Motors (as depicted in FIG. 1 as the symbol) are also connected to firstwater supply pump 1120 a and second water supply pump 1120 b, forregulating the operation of the water supply pumps, as required; motorsare communicative with and controlled by PLC 1400. In other embodiments,different combinations of valves may be disposed at different locationsalong water line 1110 in first sub-system 1100. Disposed within firstsub-system 1100 are a plurality of flowmeters and pressure indicatorsfor monitoring flow of water through first sub-system 1100 and pressureexperienced within first sub-system 1100 during operation. Eachflowmeter and pressure indicator is communicative with PLC 1400. Inother embodiments, there may not be flowmeters and pressure indicatorsin the first sub-system. Disposed within first sub-system 1100 are aplurality of frequency converters 1108, each equipped with a “start andstop” function 1108 a, a “run” function” 1108 b, and a “speedregulation” function 1108 c, and each being communicative with PLC 1400and for relaying signals and commands to the various components withinthe system 1000 and for regulating specific functions thereof. In otherembodiments, additional frequency converters may be disposed at othersuitable locations within the first sub-system.

The water intake sub-system may be similar in function to a water inletcircuit as known in the art such as but not limited toPCT/EP2009/063961.

Polymer Intake Sub-System

As contemplated in this embodiment, polymer intake sub-system 1200 isthe second sub-system of system 1000. Sub-system 1200 comprises: (i) afirst conveying unit 1210; (ii) a containing unit 1220; (iii) a feederunit 1230; and (iv) a second conveying unit 1240.

First conveying unit 1210 is used for conveying a dry material (e.g. drypolymer powder) from a dry material source (e.g. bulk tankers “A”) tocontaining unit 1220. As contemplated in this embodiment, firstconveying unit 1210 is a pneumatic conveying unit that comprises an airfilter 1210 a, a feed fan 1210 b, and an air dryer 1210 c. In otherembodiments, the first conveying unit does not comprise an air dryer. Inother embodiments, the first conveying unit 1210 can be another unitthat is known in the art. Non-limiting examples of such units includeair blowing units, pneumatic transferring units, and auger units. Firstconveying unit 1210 and containing unit 1220 are coupled to each otherby conduit 1210 d. Bulk tankers “A” are for directing dry material intoconduit 1210 d, and first conveying unit 1210 is for inducing movementof the dry material through conduit 1210 d and towards conveying unit1220. The interior surface of conduit 1210 d (as well as other conduitsconnecting different components of second sub-system 1200 together) iscoated with a coating that lessens the likelihood of “clumping” of drymaterial within the conduit. Non-limiting examples of suitable coatingsinclude “non-stick” coatings. Non-limiting examples of “non-stick”coatings include fluorinated coatings and perfluorinated coatings (e.g.Teflon™). As contemplated in this embodiment, the temperature of theconduits connecting different components of second sub-system 1200together is also regulated by a heating unit (not shown) that iscontrolled by PLC 1400. The temperature of the conduits can be regulatedat a temperature where the likelihood of “clumping” of dry materialwithin the conduits is lessened. In other embodiments, the secondsub-system does not comprise a heating unit.

Containing unit 1220 is used for storing a dry material (e.g. drypolymer powder) which has been delivered to containing unit 1220 viaconduit 1210 d. Containing unit 1220 further comprises one or more levelgauges 1220 a for monitoring and checking the amount of materialdelivered through containing unit 1220 and one or more vibrator 1220 bfor improving consistency of material delivered through container 1220.As contemplated in this embodiment, containing unit 1220 is modelWD-GF-1800 and has a capacity of greater than 300 litres, Ascontemplated in this embodiment, level gauges 1220 a is a USA Standardlevel meter. As contemplated in this embodiment, vibrator 1220 b is aUSA Standard vibrator. In other embodiments, the containing unit, thelevel gauge, and the vibrator may be another suitable level gauge andvibrator known in the art. In other embodiments, the containing unitdoes not comprise a level gauge.

Coupled to containing unit 1220 is a dust extraction unit 1220 c. A dustextraction unit is used for collecting dry material dust that is unableto settle in containing unit 1220 and for directing at least a portionof such dust back into second sub-system 1200 at second conveying unit1240. The feature advantageously improves the direction of dry materialto towards the Unit 1220 c can be coupled to second conveying unit 1240by conduit 1220 d. One or more suitable valves (e.g. disc valve) can bedisposed within conduit 1220 d for regulating the flow and amount of drymaterial dust back into second sub-system 1200. In other embodiments,the dust extraction unit can be any suitable dust extraction unit knownin the art. In other embodiments, sub-system 1200 does not comprise adust extraction unit.

Containing unit 1220 comprises an egress that is connected to an ingressof feeder unit 1230 by way of a conduit (not numbered), disposed withinwhich is a valve (as depicted in FIG. 1). Depending on whether the valveis in its “open” state or its “closed” state, the egress of containingunit 1220 can be in fluid communication with the ingress of feeder unit1230. Feeder unit 1230 is used for regulating the amount of dry materialthat is directed toward second conveying unit 1240. As contemplated inthis embodiment, feeder unit 1230 is a screw feeder. In otherembodiments, the feeder unit can be any suitable feeder unit that isknown in the art.

The speed at which screw feeder 1230 operates is controlled by PLC 1400.Namely, PLC 1400 provides instructions to frequency converter 1108 thatis coupled to a motor that drives feeder unit 1230, the frequencyconverter 1108 regulating the function of the motor connected to feederunit 1230. Feeder unit 1230 further comprises an egress through whichdry material is extruded. The egress of feeder unit 1230 is in fluidcommunication with a hopper, which in turn is in fluid communicationwith second conveying unit 1240. In other embodiments, the egress offeeder unit 1230 is in direct and fluid communication with secondconveying unit 1240.

Second conveying unit 1240 is used for directing dry material towardeductor mixing device 1300. As contemplated in this embodiment, secondconveying unit 1240 is a pneumatic conveying unit, such as one known inthe art. In other embodiments, second conveying unit 1240 can be anysuitable conveying unit that is known in the art. Second conveying unit1240 also comprises a level gauge 1240 a for use in regulating drymaterial flow consistency.

Disposed within second sub-system 1200 are a plurality of valves thatare each communicative with PLC 1400. As depicted in FIG. 1: (i) a ballvalve 1103 is disposed in the conduit that couples containing unit 1220to feeder unit 1230; and (ii) a disc valve 1105 that is disposed inconduit 1220 d. In other embodiments, different combinations of valvesmay be disposed at different locations within second sub-system 1200.Disposed within second sub-system 1200 are a plurality of level gaugesfor regulating dry material flow consistency, each of which iscommunicative with PLC 1400. Disposed within second sub-system 1200 is afrequency converter 1108 that is equipped with a “start and stop”function 1108 a, a “run” function” 1108 b, and a “speed regulation”function 1108 c, and that is communicative with PLC 1400 and forrelaying signals and commands to various components within system 1000and for regulating the functions thereof, In other embodiments,additional frequency converters may be disposed at other suitablelocations within the second sub-system.

The polymer intake sub-system may be similar to a materials transfersub-system as known in the art such as but not limited toPCT/EP2009/063961.

Eductor Mixing Device

Eductor mixing device 1300 comprises two ingress locations: (i) one influid communication with the egress of second conveying unit 1240; and(ii) one in fluid communication with water line egress 1110 b. Eductormixing device 1300 can be any suitable eductor mixing device describedin the art. Examples of eductor mixing devices include, but are notlimited to, those described in U.S. Pat. No. 4,186,772 to Handlernan etal., U.S. Pat. No. 4,884,925 to Kemp et al., and U.S. Pub. No.2005/0111298 to Lott.

Eductor mixing device 1300 provides a means for mixing a fluid (e.g.water) and a solid material (e.g. polymer powder) together in a vortexto create a mother solution. Advantageously, eductor mixing device 1300lacks the plurality of mechanical components that polymer slicing unitstypically have, thereby decreasing the likelihood of mechanical failureof mechanical parts over time due to wear and tear. Advantageously,eductor mixing device 1300 can produce mother solutions with a highconcentration (up to about 5%) of polymer content than could otherwisebe produced by using a polymer slicing unit, and can process highvolumes of dry polymer. Advantageously, eductor mixing devices generallyoccupy a smaller area and volume than polymer slicing units, and aretherefore amenable to mobile polymer dispersion systems with highprocessing capacities. As contemplated in this embodiment, eductormixing device 1300 has capacity to produce about 100 m³ per hour ofmother solution with a polymer concentration of up to about 5%.

As contemplated in this embodiment, a second eductor mixing device (notshown or numbered) is provided and serve as a “back-up” to eductormixing device 1300 in the event that eductor mixing device 1300 is takenoffline, for example for repair, maintenance, or trouble-shooting.Eductor mixing device 1300 is reversibly coupled to sub-systems 1100 and1200 via camlock fitting, thereby permitting ease of replacing saideductor mixing device with a “back-up” eductor mixing device. Inpractice, and if eductor mixing device 1300 requires to be exchanged,the flow of water from sub-system 1100 to eductor mixing device 1300 andthe flow of dry material from sub-system 1200 to eductor mixing device1300 are stopped (as regulated by PLC 1400 in a manner known in theart). Solution buffer tanks (not shown) which hold an excess of “mothersolution” (as such term is used in this specification) is coupled totank assembly 1310 and such excess “mother solution” is delivered intotank assembly 1310 to ensure constant delivery of “mother solution”downstream to units 1320/1330 while eductor mixing device 1300 isreplaced. Once the “back-up” eductor mixing device is installed andcam-locked into coupling with sub-systems 1100 and 1200, flow of “mothersolution” from solution buffer tanks into tank assembly 1310 is stoppedby control via PLC 1400, and the flow of water from sub-system 1100 tothe eductor mixing device and the flow of dry material from sub-system1200 to the eductor mixing device is initiated.

As contemplated in another embodiment, a second eductor mixing device(not shown or numbered) is provided and serve as a “back-up” to eductormixing device 1300 in the event that eductor mixing device 1300 is takenoffline, for example for repair, maintenance, or trouble-shooting.Although not shown, it is contemplated that egress 1110 b has aplurality of sub-outlets: one directed to and coupled with eductormixing device 1300 and one directed to and coupled with the secondeductor mixing device (not shown or numbered). Water flow from egress1110 b is directed to either one or both of the eductor mixing devicesby the opening and closing of valves as controlled by PLC 1400 bymethods known in the art, Although not shown, it is also contemplatesthat the egress of second conveying unit 1240 has a plurality ofsub-outlets: one directed to and coupled with eductor mixing device 1300and one directed to and coupled with the second eductor mixing device(not shown or numbered). Dry material exiting second conveying unit 1240is directed to either one or both of the eductor mixing devices by theopening and closing of valves as controlled by PLC 1400 by methods knownin the art.

Eductor mixing device 1300 has an egress that is in fluid communicationwith a tank assembly 1310. The tank assembly 1310 is used for containinga mother solution, Tank assembly 1310 comprises a plurality ofaccessories such as a liquid level meter 1312 for monitoring a level ofpolymer suspension contained in tank assembly 1310, and an overflow pipe1314 for removing excess mother solution from tank assembly 1310. Ascontemplated in this embodiment, tank assembly 1310 has a volume ofgreater than 300 litres. In other embodiments, the tank assembly may beany suitable tank assembly known in the art.

Tank assembly 1310 is coupled to a transfer sub-system by a conduit (notnumbered), the transfer sub-system comprising first transfer pump 1320and a second transfer pump 1330, The conduit comprises a first portionthat is directed and coupled to first pump 1320, and a second portionthat is directed and coupled to a second pump 1330. A plurality ofvalves is disposed in the conduit, with at least one valve beingdisposed in the first portion and at least one valve being disposed inthe second portion. The valves are for use in controlling (includingpreventing) flow of material (e.g. mother solution) into first transferpump 1320 and second transfer pump 1330.

As contemplated in this embodiment, first transfer pump 1320 is a lowshear screw pump with a pump volume capacity to pump 10 m³ of mothersolution per hour and an operable pressure setting between 0 to 150 PSI.For example, first transfer pump 1320 is operable between about 10 andabout 140 PSI, about 10 and about 120 PSI, about 10 and about 100 PSI,about 10 and about 80 PSI, about 10 and about 60 PSI, about 10 and about40 PSI, about 10 and about 30 PSI, about 10 and about 20 PSI, 0 andabout 60 PSI, 0 and about 50 PSI, 0 and about 40 PSI, 0 and about 30PSI, 0 and about 20 PSI, 0 and about 15 PSI, and 0 and about 10 PSI. Ascontemplated in this embodiment, second transfer pump 1330 is a lowshear screw pump with a pump volume capacity to pump 40 m³ of mothersolution per hour and an operable pressure setting between 0 to 150 PSI.For example, second transfer pump 1330 is operable between about 30 andabout 150 PSI, about 50 and about 150 PSI, about 70 and about 150 PSI,about 90 and about 150 PSI, about 100 and about 150 PSI, about 110 andabout 150 PSI, about 120 and about 150 PSI, about 130 and about 150 PSI,and 140 and about 150 PSI. For example, first transfer pump 1320 mayoperate at a pressure of between about 0 and about 50 PSI and secondtransfer pump 1330 may operate at a pressure of between 70 and about 150PSI. For example, first transfer pump 1320 may operate at a pressure ofbetween about 0 and about 30 PSI and second transfer pump 1330 mayoperate at a pressure of between 90 and about 150 PSI. For example,first transfer pump 1320 may operate at a pressure of between about 0and about 50 PSI and second transfer pump 1330 may operate at a pressureof between 110 and about 150 PSI.

By utilizing pumps with different pump capacities, system 1000 can beadapted to direct “mother solution” either directly to a downstreammissile unit (not shown and which is adapted for use in downholetracking operations), a downstream blender unit (not shown), or both,and therefore split-flow operations. As contemplated in this embodiment,the valves disposed in the conduit are disc valves. In otherembodiments, the valves can be any suitable valves known in the art. Inother embodiments, the first transfer pump can be any suitable lowshear, low pressure pump known in the art. In other embodiments, thesecond transfer pump can be any suitable low shear pump known in theart.

First transfer pump 1320 and second transfer pump 1330 can beoperational one at a time. In such a set up, and as an improvement to asingle pump design where the entire system would have to be put“offline” if repairs or maintenance to such single pump is required,first transfer pump 1320 and second transfer pump 1330 can serve as“back-ups” to one another, in the event that one of them becomesinoperable or is taken “offline” (e.g. for maintenance, repair, or otherreasons).

As contemplated in this embodiment, however, first transfer pump 1320and second transfer pump 1330 are operated at the same time. The egressof first transfer pump 1320 is coupled to conduit 1320 a. Conduit 1320 ais also coupled to a downstream unit such as a blender unit (not shown),a missile unit (not shown), or both. Conduit 1320 a comprises one ormore pressure monitors 1320 b for measuring the fluid pressure of mothersolution exiting first transfer pump 1320, a plurality of valves, andone or more flowmeters 1320 c for measuring the flow rate of mothersolution through conduit 1320 a. As contemplated in this embodiment,flowmeter 1320 c is an electromagnetic flowmeter. In other embodiments,the flowmeter can be any suitable flowmeter in the art. The egress ofsecond transfer pump 1330 is coupled to conduit 1330 a. Conduit 1330 ais also coupled to a downstream unit such as a blender unit (not shown),a missile unit (not shown), or both. Conduit 1330 a comprises one ormore pressure monitors 1330 b for measuring the fluid pressure of mothersolution exiting second transfer pump 1330, a plurality of valves, andone or more flowmeters 1330 c for measuring the flow rate of mothersolution through conduit 1330 a. As contemplated in this embodiment,flowmeter 1330 c is an electromagnetic flowmeter. In other embodiments,the flowmeter can be any suitable flowmeter in the art.

Operating first transfer pump 1320 and second transfer pump 1330 at thesame time permits the simultaneous production of two media, both ofwhich may be used in downhole fracturing operations: (i) a solution thatis predominantly the “mother solution” which may be directly deliveredto the missile unit as a polymer hydraulic fracturing fluid downhole foruse in a hydraulic fracturing operation; and (ii) a mixture that iscreated in the blender unit and that comprises “mother solution” andother components like sand, said mixture forming a polymer hydraulicfracturing fluid downhole for use in a hydraulic fracturing operation.By splitting the flow of “mother solution” between first transfer pump1320 and second transfer pump 1330, where the majority of the “mothersolution” flowing from the tank assembly 1310 is directed to secondtransfer pump 1330, an operator of system 1000 is able to introduce“mother solution” through first transfer pump 1320 into the blender unit(not shown) at a manner that minimizes the evolution of air bubbles as“mother solution” is mixed with sand in the blender unit. Without asplit-flow system, a build up of air bubbles could potentially occurduring the mixing of the “mother solution” and sand in the blender unit.Entrained air bubbles in the mixture would lead to potential enginecavitation and potential premature failure of downhole fracturingequipment. The mixture in the blender unit forming the polymer hydraulicfracturing fluid can then be directed to the missile for use in ahydraulic fracturing operation. In other versions of the system, themother solution is the polymer hydraulic fracturing fluid a the mothersolution does not undergo further mixing), and the mother solution isdelivered directly to the missile unit and not further blended in theblender unit.

System 1000 is operated by programmable logic controller 1400.Programmable logic controller 1400 can be any PLC known in the art. Thepurpose of programmable logic controller 1400 is also known in the art,and comprises controlling and monitoring the function and performance ofsystem 1000 as well as diagnosing and trouble-shooting potentialoperational issues of system 1000. As contemplated in this embodiment,PLC 1400 is comprises control configuration software, networkcommunication software (e.g. EASYACCESS™), development and operationsoftware, and at least two levels of control: (i) manual control andoperation of system 1000; and (ii) local monitoring of the variouscomponents within system 1000 and automatic operation thereof.

Operation of System 1000

PLC 1400 is responsible for controlling and monitoring the function andperformance of system 1000 and component parts (e.g. valves, pumps,mixing devices, filters, meters) thereof as well as diagnosing andtrouble-shooting potential operational issues of system 1000. Asdepicted in FIG. 1 via stippled lines, PLC 1400 is adapted to becommunicative with each of the various components of system 1000 for atleast the purposes of monitoring the flow and volume of materials movedthrough system 1000, controlling the manufacturing of a mother solution,and managing the operation of system 1000. For example, PLC 1400 iscommunicative with frequency converters 1108 for the purposes ofcontrolling the “start and stop” functions 1108 a, “run” functions 1108b, and “speed regulation” functions 1108 c of various components insystem 1000. PLC 1400 monitors, automates, trouble-shoots, and controlssystem 1000 in a manner that would be understood in the art. PLC 1400has a manual override function to allow an operator to manuallymanipulate the parameters of PLC 1400, if necessary (e.g. during anemergency situation).

As contemplated in this embodiment, water (and in other embodiments,more generally, a solvent) is introduced into inlet 1110 a and flowsthrough first water line segment 1111. The valves (e.g. disc valves)disposed in second water line segment 1112 are in an “open” state,thereby permitting the passage of the water from first water linesegment 1111 through second water line segment 1112 and into first watersupply pump 1120 a and towards fourth water line segment 1114. Thevalves (e.g. disc valves) disposed in third water line segment 1113 arein an “closed” state, thereby preventing the passage of the waterthrough third water line segment 1113 and into second water supply pump1120 b and towards fourth water line segment 1114.

In the event that first water supply pump 1120 a needs to be taken“offline” for repairs, maintenance, or other reason, or in the eventthat second water line segment 1112 needs to be taken “offline” forrepairs, maintenance, or other reason, PLC 1400 provides a signal to thevalves disposed in second water line segment 1112 to switch to a“closed” state, thereby preventing the passage of the water throughsecond water line segment 1112 and into first water supply pump 1120 a,PLC 1400 provides a signal to the valves disposed in third water linesegment 1113 to switch to an “open” state, thereby permitting thepassage of the water through third water line segment 1113 and intosecond water supply pump 1120 b and towards fourth water line segment1114, When second water line segment 1112 is ready to come back“online”, then PLC 1400 provides a signal to the valves disposed inthird water line segment 1113 to switch to a “closed” state, and PLC1400 provides another signal to the valves disposed in second water linesegment 1112 to switch to an “open” state.

As contemplated in this embodiment, at any given time only one of secondwater line segment 1112 and third water line segment 1113 permits thepassage of water from first water line segment 1111 to fourth water linesegment 1114. In other embodiments, this may not be the case.

Water from second water line segment 1112 or third water line segment1113, or both second water line segment 1112 and third water linesegment 1113, flows into and through fourth water line segment 1114.

The valves (e.g. disc valves) disposed in fifth water line segment 1115are in an “open” state, thereby permitting the passage of the water fromfourth water line segment 1114 through fifth water line segment 1115,through filter 1130 a, and towards seventh water line segment 1117. Thevalves (e.g. disc valves) disposed in sixth water line segment 1116 arein an “closed” state, thereby preventing the passage of the waterthrough sixth water line segment 1116, through filter 1130 b, andtowards seventh water line segment 1117.

In the event that filter 1130 a needs to be taken “offline” for repairs,maintenance, or other reason, or in the event that fifth water linesegment 1115 needs to be taken “offline” for repairs, maintenance, orother reason, PLC 1400 provides a signal to the valves disposed in fifthwater line segment 1115 to switch to a “closed” state, therebypreventing the passage of the water through fifth water line segment1115 and into filter 1130 a. PLC 1400 provides a signal to the valvesdisposed in sixth water line segment 1116 to switch to an “open” state,thereby permitting the passage of the water through sixth water linesegment 1116 and into second water supply pump 1130 b and towardsseventh water line segment 1117. When fifth water line segment 1115 isready to come back “online”, then PLC 1400 provides a signal to thevalves disposed in sixth water line segment 1116 to switch to a “closed”state, and PLC 1400 provides another signal to the valves disposed infifth water line segment 1115 to switch to an “open” state. In otherembodiments, water flows through both fifth water line segment 1115 andsixth water line segment concurrently.

Water flows through seventh water line segment 1117 and towards outlet1110 b and eductor mixing device 1300. Seventh water line segment 1117comprises a plurality of instruments including one or more pressuredifference monitors, one or more flow meters, and one or more valves. Ifthe one or more pressure monitors detect a water pressure in seventhline segment that exceeds a pre-defined maximum value or is below apre-defined minimum value, then PLC 1400, by means known in the art,provides signals to appropriate components through water line 1110 forthe purpose of appropriately adjusting the detected pressure differencewithin seventh water line segment 1117. If the one or more flowmetersdetect a water flow rate that exceeds a pre-defined maximum value or isbelow a pre-defined minimum value, then PLC 1400, by means known in theart, provides signals to appropriate components through water line 1110for the purpose of appropriately adjusting the water flow rate withinseventh water line segment 1117.

Water exits water line 1110 through outlet 111 Ob and into eductormixing device 1300.

Concurrently with water flowing through water line 1110, dry polymer foruse as an ingredient of a mother solution (in other embodiments, moregenerally, a dry material) is delivered into conduit 1210 d from bulktankers “A”, and conveyed into containing unit 1220 through conduit 1210d. Dry polymer is moved through conduit 1210 d by first conveying unit1210. PLC 1400 controls the settings of first conveying unit 1210, andsuch control dictates the speed and volume at which dry polymer movesthrough conduit 1210 d.

Dry polymer exits an egress of conduit 1210 d and into containing unit1220, and accumulates within containing unit 1220. Level gauges 1220 amonitor the amount of dry polymer accumulating in containing unit 1220and the height to which dry polymer has accumulated in containing unit1220. For example, if a level gauge 1220, detects that a height to whichdry polymer has accumulated in containing unit 1220 has exceeded apre-determined maximum height, or that the amount of dry polymeraccumulated in containing unit 1220 has exceeded a pre-determinedmaximum weight, then PLC 1400 signals to first conveying unit 1210 tostop conveying dry polymer through conduit 1210 d and into containingunit 1220. One or more vibrators 1220 b also assist in providing an evendistribution of dry polymer in the containing unit 1220. One or morevibrators 1220 b also work with dust extraction unit 1220 c, operatingby negative pressure, to render dry polymer dust airborne withincontaining unit 1220 so that it may be introduced by negative pressureinto dust extraction unit 1220 c. Through conduit 1220 d, dustextraction unit 1220 c then returns such dry polymer dust back intosecond sub-system 1200 at second conveying unit 1240.

Dry polymer is conveyed from containing unit 1220 into feeder unit 1230through a conduit (un-numbered) connecting containing unit 1220 tofeeder unit 1230. The flow of dry polymer through the conduit isdetermined by the operational setting (e.g. “open”, “closed”, “halfopen”) of the valve (e.g. ball valve), as controlled and monitored byPLC 1400. Dry polymer is moved through feeder unit 1230 and into secondconveying unit 1240, and, by pneumatic means, the dry polymer isdirected to eductor mixing device 1300 from second conveying unit 1240.

Eductor mixing device 1300 receives dry polymer from second conveyingunit 1240 and water from water line 1110 by means of negative pressure.The operations of an eductor mixing device is known in the art, anddescribed in U.S. Pat. No. 4,186,772 to Handleman et al., U.S. Pat. No.4,884,925 to Kemp et al, and U.S. Pub. No. 2005/0111298 to Lott. Byusing an eductor mixing device in system 1000, a polymer solution withhigh dry polymer concentration (up to about 90% active polymer) can becreated. This can be compared with industry standards of polymeremulsion comprising about 30% to 35% active polymer.

The produced mother solution is delivered into tank assembly 1310, andpermitted to “mature” therein. If an excess of mother solution isdelivered into tank assembly 1310, then the excess mother solution isremoved from tank assembly 1310 through overflow pipe 1314. Overflowpipe 1314 is connected to sewage outlet “S” or an external holding tank(not shown).

The produced mother solution is introduced from tank assembly 1310 tofirst transfer pump 1320 and second transfer pump 1330 via a conduitwhich comprises a first portion that feeds into first transfer pump 1320and a second portion that feeds into second transfer pump 1330. Shouldthe flow of mother solution into either first transfer pump 1320, secondtransfer pump 1330, or both be above or below a pre-determined optimalflow range as monitored by PLC 1400, then the state (e.g. “closed”,“open”, “half-open”, “quarter-open”) of the valves (e.g. disc valves)disposed in the conduit is adjusted accordingly by PLC 1400.

As contemplated in this embodiment, first transfer pump 1320 and secondtransfer pump 1330 can serve as “back-ups” for one another in the eventthat one of them needs to be taken “offline”. That being said, and ascontemplated in this embodiment, first transfer pump 1320 and secondtransfer pump 1330 are different in that first transfer pump 1320 is alow pressure pump that is connected to a blender system (not shown) andthat second transfer pump 1330 is a high pressure pump that can beconnected to either a blender system or directly into a missile system(not shown) for downhole application. Advantageously, system 1000 whichcomprises a dual functionality of a low pressure transfer pump 1320 anda high pressure transfer pump 1330 permits an operator to seamlesslytransition from one application (combination with a blender system) toanother application (combination with a missile system) in the fieldwithout added equipment.

Mother solution is extruded from first transfer pump 1320 and intoconduit 1320 a. The fluid pressure of mother solution exiting firsttransfer pump 1320 is determined by pressure gauge 1320 b. If thepressure is above or below a pre-determined suitable operationalpressure range, then PLC 1400 adjusts the settings of the system 1000 tobring the pressure back within the suitable operational pressure range.The flow rate of mother solution through conduit 1320 a is alsomonitored by flow meter 1320 c. If the flow rate is above or below apre-determined suitable operational flow rate, then PLC 1400 adjusts thesettings of the system 1000 to bring the flow rate back within thesuitable range.

Mother solution is extruded from second transfer pump 1330 and intoconduit 1330 a. The fluid pressure of mother solution exiting secondtransfer pump 1330 is determined by pressure gauge 1330 b. If thepressure is above or below a pre-determined suitable operationalpressure range, then PLC 1400 adjusts the settings of the system 1000 tocorrect the pressure and lower it to within range of the suitableoperational pressure range. The flow rate of mother solution throughconduit 1330 a is also monitored by flow meter 1330 c. If the flow rateis above or below a pre-determined suitable operational flow rate, thenPLC 1400 adjusts the settings of the system 1000 to bring the flow rateback within the suitable range,

In other embodiments, both conduits 1320 a and 1330 a are connected to ablender unit (not shown) and missile unit (not shown). The flow ofmother solution into the blender unit, missile unit, or both, iscontrolled by PLC 1400.

The blender unit (not shown) receives and mixes mother solution and sandtogether in a desired ratio to form a polymer hydraulic fracturingfluid. Such fracturing fluid is then delivered into a missile unit (notshown) for injecting fracturing fluid downhole. In some embodiments, theblender unit is not used, and mother solution is the polymer hydraulicfracturing fluid. In such embodiments, mother solution is introduceddirectly into the missile system from either conduit 1320 a or conduit1330 a.

General

It is contemplated that any part of any aspect or embodiment discussedin this specification may be implemented or combined with any part ofany other aspect or embodiment discussed in this specification. Whileparticular embodiments have been described in the foregoing, it is to beunderstood that other embodiments are possible and are intended to beincluded herein. It will be clear to any person skilled in the art thatmodification of and adjustment to the foregoing embodiments, not shown,is possible.

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as is commonly understood by one of ordinary skillin the art to which this invention belongs. In addition, any citation ofreferences herein is not to be construed nor considered as an admissionthat such references are prior art to the present invention.

The scope of the claims should not be limited by the example embodimentsset forth herein, but should be given the broadest interpretationconsistent with the description as a whole.

1. A system for use in a hydraulic fracturing operation, the systemcomprising: (a) tank assembly comprising a first ingress, a secondingress, an egress, and an interior volume for collecting mothersolution; (a) a first sub-system comprising an ingress and an egress,and configured to receive liquid medium; (b) a second sub-systemcomprising an ingress and an egress, and configured to receiveparticulate material; (c) an eductor mixing device comprising (i) afirst inlet coupled with the egress of the first sub-system, (ii) asecond inlet coupled with the egress of the second sub-system, and (iii)an egress coupled with the first ingress of the tank assembly, theeductor mixing device, when activated, being capable of generating anegative pressure for drawing liquid medium and particulate materialinto it and mixing said liquid medium and said particulate material byvortex for forming mother solution; (d) a storage container forcollecting and storing excess mother solution, the storage containercomprising an egress that is coupled to the second ingress of the tankassembly, and that can be in fluid communication with the interiorvolume of the tank assembly; (f) a first transfer pump coupled with theegress of the tank assembly; and (g) a second transfer pump coupled withthe egress of the tank assembly.
 2. The system as claimed in claim 1,wherein the first transfer pump is coupled to both a missile unit and ablender unit downstream thereof but in fluid communication with only oneof such units at any given time, and wherein the second transfer pump iscoupled to both the missile unit and the blender unit downstream thereofbut in fluid communication with only one of such units at any giventime.
 3. The system as claimed in claim 1, the tank assembly furthercomprising a liquid level meter for regulating the volume of mothersolution flowing towards the first transfer pump, the second transferpump, or both.
 4. The system as claimed in claim 1, wherein the firsttransfer pump and the second transfer pump each operates at a pressurebetween 0 and 150 PSI.
 5. The system as claimed in claim 1, the firstsub-system comprising a plurality of water line segments that areinterconnected and for transporting liquid medium, at least two of suchwater line segments being positioned in parallel to one another, atleast two of such waterline segments being positioned in series to oneanother, and a first pump disposed along a first water line segment thatis a part of the plurality of water line segments and a second pumpdisposed along a second water line segment that is a part of theplurality of water line segments, the first pump and the second pumpbeing positioned in parallel to one another.
 6. The system as claimed inclaim 5, each of the water lines comprising one or more valves forregulating the flow of the liquid medium therethrough.
 7. The system asclaimed in claim 5, the first sub-system further comprising a firstfilter disposed in a third water line segment that is a part of theplurality of water line segments and a second filter disposed in afourth water line segment that is a part of the plurality of water linesegments, the first filter and the second filter being positioned inparallel to one another.
 8. The system as claimed in claim 1, the secondsub-system comprising: (a) a containing unit comprising an ingress andan egress; (b) a feeder unit comprising an ingress that is in fluidcommunication with the egress of the containing unit via a conduit; and(c) a conveying unit in fluid communication with an egress of the feederunit, the conveying unit configured for receiving material from thefeeder unit, the conveying unit in fluid communication with the eductormixing device.
 9. The system as claimed in claim 8, the containing unitfurther comprising: (a) a level meter for controlling the volume ofparticulate material passing through the egress of the containing unitand into the feeder unit; and (b) a vibrator for agitating particulatematerial that is contained in the containing unit.
 10. The system asclaimed in claim 8, wherein the feeder unit is a screw feeder.
 11. Thesystem as claimed in claim 8, wherein the conveying unit is a pneumaticconveying unit.
 12. The system as claimed in claim 8, wherein theconveying unit is in fluid communication with a dust collection unit,the dust collective unit for receiving any particulate material that isnot received into the feeder unit.
 13. The system as claimed in claim 8,wherein the eductor mixing device is in fluid communication with theconveying unit.
 14. The system as claimed in claim 8, wherein aninterior surface of one or more parts of the second sub-system is coatedwith a non-stick coating.
 15. The system as claimed in claim 8, whereinone or more parts of the second sub-system is coupled to a heatingdevice.
 16. The system as claimed in claim 1, the tank assembly furthercomprising an overflow pipe having an ingress that is in fluidcommunication with the interior volume of the tank assembly, theoverflow pipe for receiving excess mother solution that cannot becontained within the tank assembly.
 17. The system as claimed in claim1, further comprising a programmable logic controller configured tocontrol the system and functionality thereof.
 18. A method of operatingthe system as claimed in claim 1, the method comprising: (a) receivingliquid medium in the first sub-system; (b) receiving particulatematerial in the second sub-system; (c) transporting liquid medium andparticulate material into the eductor mixing device; (d) mixing liquidmedium and particulate material by vortex to form the mother solution;and (e) transporting the mother solution to the first transfer pump, thesecond transfer pump, or both.
 19. The system as claimed in claim 1,wherein the second transfer pump has a pump volume capacity that isgreater than the first transfer pump, wherein the second transfer pumpis configured to operate at a higher pump pressure than the firsttransfer pump, and wherein the first pump and the second transfer pumpare operational one at a time to permit continuous operation of thesystem when one of the first and second transfer pumps is offline. 20.The system as claimed in claim 16, wherein the overflow pipe has anegress that is coupled to an ingress of the storage container, and thatcan be in fluid communication with an interior volume of the storagecontainer.